Here is a link where change expression of genes in the brain for rate fed high fish oil or high perilla diets is shown by reference to a standard diet.
The trials are looking at the impact of fats on the brain ageing alzheimer's etc. This is one of many in the general subject area.
I have no idea as to the significance of various genes.
I just post the chart to try and illustrate the point that changes in diet and particularly fats can alter the ways our bodies work even in the way we use the genetic ingredients available to us.
Significantly
In numerous subtle ways
At very fundamental levels
Different recipe for different cakes some of which will work and some which will not. I suspect nature is no different from cookery - go beyond certain parameters and your cake mix will not work.
http://www.pnas.org/cgi/content/full/99/5/2619/T5
and the link to the trial
http://www.pnas.org/cgi/content/full...7faf8fdb716645